Vapor chamber structure

ABSTRACT

A vapor chamber structure includes an upper plate, a lower plate, a middle layer and a polymer layer. The polymer layer is selectively connected with any of the upper and lower plates. The lower plate and the upper plate are mated with each other to together define a chamber. A working fluid is filled in the chamber. The middle layer is disposed in the chamber. The middle layer has a first face, a second face, multiple perforations and multiple channels. The multiple perforations pass through the first and second faces. The multiple channels are disposed on one of the first and second faces. By means of the above arrangement, the total thickness of the vapor chamber structure is equal to or smaller than 0.25 mm, whereby the vapor chamber can be extremely thinned.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates generally to a vapor chamber, and moreparticularly to an extremely thin vapor chamber.

2. Description of the Related Art

In order to achieve better heat transfer effect, in the heat dissipationfield, the heat dissipation device employing two-phase fluid heatexchange principle is used as the heat transfer component. In the heatdissipation devices, the vapor chamber and heat pipe are most oftenused. The vapor chamber and the heat pipe employ two-phase fluid heatexchange principle so that the main structures of the vapor chamber andthe heat pipe must be made of a material with better heat conductivity,wherein copper is the most often seen material. The main body must havean internal vacuumed airtight chamber. Also, capillary structure isdisposed on the wall face of the chamber and a working liquid is filledin the chamber. In the vacuumed environment, the boiling point of theworking liquid is lowered and two-phase fluid (vapor and liquid)circulation can be carried out in the vacuumed airtight chamber toachieve better heat transfer efficiency.

A conventional vapor chamber has a main body composed of at least oneplate body equipped with capillary structure and another plate bodymated with the at least one plate body. Then the periphery of the mainbody is sealed and water (liquid working fluid) is filled into thechamber and the chamber is vacuumed to form the vapor chamber. Thecapillary structure in the vapor chamber mainly serves to make theliquid working fluid flow from the condensation section back to theevaporation section and store the liquid working fluid in theevaporation section. The capillary structure generally has the form of asintered body, a mesh body, a fiber body and a channeled body, which isa structure capable of providing capillary attraction.

The sintered body is formed in such a manner that one face of the platebody is coated with metal powders. The metal powders are sintered andattached to the plate body to form a porous capillary structure. In thesintering process, each two adjacent powders are heated to a semi-moltenstate, whereby the powders are bonded with each other to form the porouscapillary structure. In order to keep the capillary structure of thesintered powders with the property of porosity, the size of the sinteredpowders is limited. In the case that the size of the sintered powders istoo small, after semi-molten, the sintered powders will nearly have novoid therebetween.

Under such circumstance, the sintered powders cannot form the porouscapillary structure. That is, the capillary structure cannot provide anycapillary attraction. Therefore, those fine sintered powders with toosmall size cannot be selectively used for the existing sintered body.Only those sintered powders with proper size can be sintered to form thecapillary structure with voids between the powders to achieve capillaryattraction. However, in this case, the sintered structure will bethickened. As a result, the conventional sintered body cannot be appliedto an extremely thinned vapor chamber structure. Moreover, the currentvapor chamber employing sintered body cannot be partially folded (bent).This is because after the vapor chamber is folded (bent), the sinteredbody in the chamber will be broken and destroyed to detach. This willlead to failure of the capillary structure on the plate body to lose theheat spreading and dissipation function.

Therefore, in order to solve the problem that the conventional sinteredbody cannot be applied to an extremely thinned vapor chamber structure,the manufacturers try to use the channeled structure with poorercapillary attraction or a mesh body or a woven mesh with capillaryattraction smaller than the sintered powders as the capillary structure.The mesh body or the woven mesh can be conveniently arranged and appliedto those parts, which need to be bent. However, when disposing the meshbody or the woven mesh in the vapor chamber, the mesh body or the wovenmesh must be fully attached to the wall of the case or the pipe so thatthe mesh body or the woven mesh can provide capillary attraction forspreading the working liquid. In the case that the mesh body or thewoven mesh fails to fully attach to the surface of the wall of the caseor the pipe, no capillary attraction is provided for the working liquidto spread and carry out vapor-liquid circulation. Also, the mesh bodyand the woven mesh are mainly composed of multiple filament-shapedmonomers, which intersect each other or which are woven with each other.Due to the limitation of the current processing machine and material,the diameter of each filament-shaped monomer (such as filament-shapedmetal wire) can be hardly further minified. Therefore, the totalthickness of the mesh body (or woven mesh) formed of the multiplefilament-shaped monomers, which intersect each other or which are wovenwith each other cannot be further reduced. As a result, the conventionalmesh body and woven mesh also cannot be applied to the extremely thinnedvapor chamber structure.

Therefore, the manufacturers can only settle for the second best toemploy the channeled structure with poorer capillary attraction. Thechanneled structure is formed in such a manner that the wall face of thecase of the vapor chamber is mechanically processed to form thechanneled structure as the capillary structure. However, this leads toanother problem that when the wall face of the case of the vapor chamberis formed with the channeled structure, the wall of the case of thevapor chamber is also thinned. This will affect the structural strengthof the entire vapor chamber so that it often takes place that the wallof the case of the vapor chamber is broken. In this case, the workingliquid will leak out to lose the heat spreading and dissipation effect.When the wall face of the case of the vapor chamber is formed with thechanneled structure, the wall of the case of the vapor chamber isthinned to weaken the structural strength of the entire vapor chamber.In the case that the vapor chamber is folded (bent), the section formedwith the channeled structure is apt to break off. In consideration ofthe above problems, the manufacturers often quit using the channeledstructure on the extremely thin vapor chamber.

Therefore, under the trend toward extremely thin vapor chamber, thetotal thickness of the vapor chamber is quite limited. The thickness ofthe wall of the case of the vapor chamber is limited to an extremelythin specification. Also, the internal airtight chamber and thecapillary structure of the vapor chamber must be further minified. Itcan be known from the above that when designing the extremely thin vaporchamber, it is critical how to select and manufacture the capillarystructure.

It is therefore tried by the applicant to provide a vapor chamberstructure to solve the above problems existing in the conventionalextremely thin vapor chamber. The vapor chamber structure can providecapillary attraction and is applicable to the extremely thin vaporchamber.

SUMMARY OF THE INVENTION

It is therefore a primary object of the present invention to provide avapor chamber structure, which is applicable to extremely thin vaporchamber.

It is a further object of the present invention to provide the abovevapor chamber structure, which has better capillary attraction and isfoldable (bendable).

To achieve the above and other objects, the vapor chamber structure ofthe present invention includes an upper plate, a lower plate, a middlelayer and a polymer layer. The lower plate and the upper plate are matedwith each other to together define a chamber. A working fluid is filledin the chamber. The middle layer is disposed in the chamber. The middlelayer has a first face, a second face, multiple perforations andmultiple channels. The multiple perforations pass through the first andsecond faces. The multiple channels are disposed on one of the first andsecond faces. The polymer layer is selectively connected with any of theupper and lower plates. The total thickness of the vapor chamberstructure is equal to or smaller than 0.25 mm.

By means of the present invention, the heat dissipation unit can beextremely thinned. In addition, the middle layer serves as the capillarystructure for vapor-liquid circulation of the vapor working fluid andthe liquid working fluid, whereby the shortcoming of the conventionalheat dissipation unit that the vapor chamber cannot be extremely thinnedis solved.

In the above vapor chamber structure, the upper plate is composed ofmultiple upper plate bodies, which are laminated with each other. Thepolymer layer is sandwiched between the multiple upper plate bodies toform the upper plate. The lower plate is composed of multiple lowerplate bodies, which are laminated with each other. The polymer layer issandwiched between the multiple lower plate bodies to form the lowerplate. The polymer layer is selectively formed on the upper inner faceor the upper outer face of the upper plate by means of painting,printing or adhesion.

The polymer layer is selectively formed on the lower inner face or thelower outer face of the lower plate by means of painting, printing oradhesion. The multiple channels are longitudinally or transversely orlongitudinally and transversely to intersect each other formed on thesecond face of the middle layer.

The vapor chamber structure further includes a hydrophilic layer. Thehydrophilic layer is selectively disposed on the upper inner face or thelower inner face or the second face of the middle layer and the surfaceof the multiple channels.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein:

FIG. 1 is a perspective exploded view of a preferred embodiment of thevapor chamber structure of the present invention; and

FIG. 2 is a sectional assembled view of the preferred embodiment of thevapor chamber structure of the present invention, in which the circledarea is enlarged.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides a vapor chamber structure. Please referto FIGS. 1 and 2. FIG. 1 is a perspective exploded view of a preferredembodiment of the vapor chamber structure of the present invention. FIG.2 is a sectional assembled view of the preferred embodiment of the vaporchamber structure of the present invention, in which the circled area isenlarged. The vapor chamber structure 1 of the present inventionincludes an upper plate 11, a lower plate 13, a middle layer 15 and apolymer layer 16. The upper plate 11 has an upper outer face 111, anupper inner face 112 and multiple bosses 113. The multiple bosses 113are disposed on the upper inner face 112 and raised therefrom. The lowerplate 13 has a lower outer face 131 and a lower inner face 132. Thelower inner face 132 is opposite to the upper inner face 112. The lowerplate 13 and the upper plate 11 are mated with each other to togetherdefine a chamber 14. A working fluid (such as pure water) is filled inthe chamber 14. The upper plate 11 and the lower plate 13 are made of amaterial selected from a group consisting of copper, aluminum, stainlesssteel and commercial pure titanium. The thickness of the upper and lowerplates 11, 13 is approximately 0.05 mm. In a preferred embodiment, thevapor chamber structure 1 can be alternatively a heat plate structure.

The middle layer 15 can be a sheet body or plate body disposed in thechamber 14. The middle layer 15 has a first face 151, a second face 152,multiple perforations 153 and multiple channels 154. The first andsecond faces 151, 152 are respectively correspondingly in contact andattachment with the lower inner face 132 and the multiple bosses 113.The multiple channels 154 are disposed on the first face 151 or thesecond face 152 or both the first and second faces 151, 152. In thisembodiment, the multiple channels 154 are arranged and disposed on thesecond face 152 of the middle layer 15 at intervals. That is, themultiple channels 154 are longitudinally and transversely formed on thesecond face 152 of the middle layer 15 to intersect each other. Thelongitudinal channels 154 are in communication with the transversechannels 154. Accordingly, under the capillary attraction of themultiple channels 154, the liquid working fluid can quickly flow alongthe longitudinal and transverse channels 154 back to the lower innerface 132, (that is, the evaporation section). The thickness of themiddle layer 15 is about such as 0.05 mm.

The multiple perforations 153 pass through the first and second faces151, 152. The multiple perforations 153 and the multiple channels 154are alternately arranged or not alternately arranged. In thisembodiment, the multiple perforations 153 and the multiple channels 154are, but not limited to, horizontally alternately arranged forillustration. Accordingly, by means of the design of the channels 154formed on one face or both faces of the middle layer 15 and theperforations 153 passing through the middle layer 15 of the presentinvention, the multiple channels 154 are for the liquid working fluid toflow back and the multiple perforations 154 serve as vapor passages forthe evaporated working fluid. Therefore, the present invention has thecapillary structure with both the vapor circulation passages and thecapillary attraction for making the liquid working fluid to flow back.This solves the problem that the capillary structure can be hardlydisposed in the narrow internal chamber 14 of the thinned heatdissipation unit. Moreover, the middle layer 15 serves as a supportstructure for the vapor chamber structure 1 so that the chamber 14 ofthe vapor chamber structure 1 can keep complete without being squeezedand deformed to lose the vapor-liquid circulation function. In amodified embodiment, the multiple perforations 153 and the multiplechannels 154 are vertically overlapped and alternately arranged. Inanother modified embodiment, the multiple channels 154 are transverselyor longitudinally formed on the second face 152 of the middle layer 15.

The polymer layer 16 is such as artificial polymer (such as PE, PVC,Nylon, Dacron, ABS and SBR) or inorganic polymer (such as quartz,asbestos, mica or graphite). The polymer layer 16 is selectivelyconnected with the upper plate 11 or the lower plate 13. The polymerlayer 16 is selectively formed on the surface (such as the surface ofthe upper outer face 111, the surface of the upper inner face 112, thesurface of the lower inner face 132 or the surface of the lower outerface 131) of the upper plate 11 or the lower plate 13 by means ofpainting, printing, adhesion or attachment. In this embodiment, thepolymer layer 16 is formed on the surface of the lower outer face 131 ofthe lower plate 13 by means of painting. The total thickness of thevapor chamber structure 1 is, but not limited to, equal to 0.25 mm. Inpractice, the total thickness of the vapor chamber structure 1 can besmaller than 0.25 mm.

In still another modified embodiment, the structure is partiallyidentical to the above embodiments and thus will not be redundantlydescribed hereinafter. The modified embodiment is different from theabove embodiments in that the polymer layer is disposed and sandwichedbetween the upper plate and/or the lower plate. In addition, the upperplate (and/or the lower plate) are composed of multiple upper platebodies (and/or multiple lower plate bodies), which are laminated witheach other.

In still another modified embodiment, the structure is partiallyidentical to the above embodiments and thus will not be redundantlydescribed hereinafter. The modified embodiment is different from theabove embodiments in that the vapor chamber structure 1 further includesa hydrophilic layer. The hydrophilic layer is selectively disposed onthe upper inner face or the lower inner face or the second face of themiddle layer and the surface of the multiple channels.

In conclusion, the various capillary structures employed by theconventional techniques are applied to the extremely thin vapor chamberunder limitation. Therefore, the vapor chamber can be hardlysuccessfully thinned. According to the design of the vapor chamberstructure 1 of the present invention, the total thickness of the vaporchamber structure 1 of the present invention is equal to or smaller than0.25 mm. Therefore, the vapor chamber structure 1 of the presentinvention effectively improves the shortcoming of the conventional vaporchamber that in the thinning process, the capillary structure cannot beextremely thinned.

The present invention has been described with the above embodimentsthereof and it is understood that many changes and modifications in suchas the form or layout pattern or practicing step of the aboveembodiments can be carried out without departing from the scope and thespirit of the invention that is intended to be limited only by theappended claims.

What is claimed is:
 1. A vapor chamber structure comprising: an upperplate having an upper outer face and an upper inner face; a lower platehaving a lower outer face and a lower inner face, the plate and theupper plate being mated with each other to together define a chamber, aworking fluid being filled in the chamber; a middle layer disposed inthe chamber, the middle layer having a first face, a second face,multiple perforations and multiple channels, the multiple perforationspassing through the first and second faces, the multiple channels beingdisposed on at least one of the first and second faces; and a polymerlayer selectively connected with any of the upper and lower plates,whereby the total thickness of the vapor chamber structure is equal toor smaller than 0.25 mm.
 2. The vapor chamber structure as claimed inclaim 1, wherein the polymer layer is selectively formed on the lowerouter face of the lower plate by means of painting, printing oradhesion.
 3. The vapor chamber structure as claimed in claim 1, whereinthe multiple channels are longitudinally and transversely formed on thesecond face of the middle layer to intersect each other.
 4. The vaporchamber structure as claimed in claim 1, wherein the multiple channelsand the multiple perforations are alternately arranged.
 5. The vaporchamber structure as claimed in claim 1, wherein the upper plate hasmultiple bosses, the multiple bosses being disposed on the upper innerface of the upper plate and raised therefrom, the second face of themiddle layer being attached to the multiple bosses.